Viewing archive of Thursday, 24 September 2015

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2015 Sep 24 1231 UTC

SIDC Forecast

Valid from 1230 UTC, 24 Sep 2015 until 26 Sep 2015
Solar flares

C-class flares expected, (probability >=50%)

Geomagnetism

Active conditions expected (A>=20 or K=4)

Solar protons

Quiet

10cm fluxAp
24 Sep 2015100014
25 Sep 2015097014
26 Sep 2015094011

Bulletin

Five active regions were reported today by NOAA. The flaring activity is below the C-level today, but seven C-class flares were detected yesterday, the strongest of them being the C3.2 flare peaking at 18:57 UT in the Catania sunspot group 39 (NOAA AR 2422). We expect flaring activity on the C-level, with a small chance for an M-class flare, in particular in the Catania sunspot group 39 (NOAA AR 2422). The Earth is currently inside a slow (around 460 km/s) solar wind flow with average (5-6 nT) interplanetary magnetic field magnitude. The geomagnetic conditions are quiet. Today we expect the arrival of a fast solar wind stream from a small equatorial coronal hole. Active to minor geomagnetic storm conditions may occur.

Today's estimated international sunspot number (ISN): 094, based on 16 stations.

Solar indices for 23 Sep 2015

Wolf number Catania082
10cm solar flux///
AK Chambon La Forêt018
AK Wingst014
Estimated Ap012
Estimated international sunspot number089 - Based on 21 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

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